package com.cnpinxi.tool;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;

/**
 * Created by Andrew  on 2016/10/19.
 */
public class RandomValidateCode {
    public static String validateCode = null;
    public static final String RANDOMCODEKEY = "RANDOMVALIDATECODEKEY";// 放到session中的key
    private Random random = new Random();
//    private String[][] randString = {{"一","二","三","四","五","六","七","八","九","十"},
//                                    {"加","减","乘"},
//                                    {"一","二","三","四","五","六","七","八","九","十"}};// 随机产生的字符串
     private String[][] randString = {{"0","1","2","3","4","5","6","7","8","9"},
                                        {"A","B","C","D","E","F","G","H","J","K","L","M","N","P","Q","R","S","T","U","V","W","X","Y","Z"},
                                      {"a","b","c","d","e","f","g","h","j","k","l","m","n","p","q","r","s","i","u","v","w","x","y","z"},};

    private int width = 80;// 图片宽
    private int height = 40;// 图片高
    private int lineSize = 0;// 干扰线数量
    private int stringNum = 4;// 随机产生字符数量

    /*
     * 获得字体
     */
    private Font getFont() {
        return new Font("Fixedsys", Font.CENTER_BASELINE, 22);
    }

    /*
     * 获得颜色
     */
    private Color getRandColor(int fc, int bc) {
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc - 16);
        int g = fc + random.nextInt(bc - fc - 14);
        int b = fc + random.nextInt(bc - fc - 18);
        return new Color(r, g, b);
    }

    /**
     * 生成随机图片
     */
    public void getRandomCode(HttpServletRequest request,
                              HttpServletResponse response) {
        //存放随机选择的数据
        int[] end=new int[3];

        HttpSession session = request.getSession();
        // BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
        BufferedImage image = new BufferedImage(width, height,
                BufferedImage.TYPE_INT_BGR);
        Graphics g = image.getGraphics();// 产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
        g.setColor(new Color(Integer.parseInt("FFA500",16)));
        g.fillRect(0, 0, width, height);
        g.setFont(new Font("微软雅黑", Font.ROMAN_BASELINE, 18));
//        g.setColor(getRandColor(110, 133));
        g.setColor(Color.WHITE);
        // 绘制干扰线
        for (int i = 0; i < lineSize; i++) {
            drawLine(g);
        }
        // 绘制随机字符
        String randomString = "";
        for (int i = 0; i <stringNum; i++) {
//            g.setColor(getRandColor(110, 133));
            randomString = drawStringTwo(g, randomString, i);
        }
        session.removeAttribute(RANDOMCODEKEY);
        //计算结果
//        int result=compute(end);
        System.out.println(randomString);
//        session.setAttribute(RANDOMCODEKEY, String.valueOf(result));
        session.setAttribute(RANDOMCODEKEY,randomString);
        g.dispose();
        try {
            ImageIO.write(image, "JPEG", response.getOutputStream());// 将内存中的图片通过流动形式输出到客户端
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     *计算结果
     */
    private  int compute(int[]end){
        switch (end[1]){
            case 0: return (end[0]+1)+(end[2]+1);
            case 1: return (end[0]+1)-(end[2]+1);
            case 2:return (end[0]+1)*(end[2]+1);
            default: return -1;
        }
    }
    /*
     * 绘制字符串
     */
    private String drawString(Graphics g, String randomString, int i,int[] end) {
        g.setFont(getFont());
//        g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
//                .nextInt(121)));
        int count = random.nextInt(randString[i].length);
        end[i]=count;
        String rand = String.valueOf(getRandomString(i,count));
        randomString += rand;
        g.translate(random.nextInt(3), random.nextInt(3));
        g.drawString(rand, 20 * i+5, 24);
        return randomString;
    }
    /*
  * 绘制字符串
  */
    private String drawStringTwo(Graphics g, String randomString, int i) {
        g.setFont(getFont());
//        g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
//                .nextInt(121)));
        int num=random.nextInt(3);
        int count = random.nextInt(randString[num].length);
        String rand = String.valueOf(getRandomString(num,count));
        randomString += rand;
        g.translate(random.nextInt(3), random.nextInt(3));
        g.drawString(rand, 13 * i+5, 24);
        return randomString;
    }

    /*
     * 绘制干扰线
     */
    private void drawLine(Graphics g) {
        int x = random.nextInt(width);
        int y = random.nextInt(height);
        int xl = random.nextInt(13);
        int yl = random.nextInt(15);
        g.drawLine(x, y, x + xl, y + yl);
    }

    /*
     * 获取随机的字符
     */
    public String getRandomString(int i,int num) {
        return String.valueOf(randString[i][num]);
    }
}
